Lubricants



Patented Feb. 13, 1945 LUBRICANTS Eugene Lieber, West New Brighton, Staten Island, N. Y., and Aloysius F. Casbman, Bayonne, N. J., assignors to Standard Oil Development Company, a corporation of Delaware No Drawing. Application December 31, 1941, Serial No. 425,126

3 Claims. 252-48) This invention relates to the field of lubricants and more particularly to stabilized extreme pressure lubricants.

It is known that plain mineral oils do not have a sufiiciently high film strength for lubricating under high pressures such as certain types of bearings, engines, gears, etc. It is also known, that the film strengthor load-carrying capacity of such mineral oils can be greatly increased by 10 adding thereto various chemical compounds or materials containing active halogen and/or sulfur, and sometimes phosphorus, but these various materials, although very effective in carrying the high loads demanded of extreme pressure lubricants, have a serious disadvantage that during storage, especially in contact with certain metals such as iron, they undergo some type of degradation or change which tend to make certain constituents thereof insoluble and precipitate out. go It has now been found that the addition of small amounts of certain types of materials to the extrem pressure lubricating agents or to the lubricants in which they are compounded, will stabilizethem against such tendencies to form an 5 insoluble precipitate or sediment. With this primary object in view, another object of the invention is to accomplish this desired stabilization without interfering or materially reducing the extreme pressure lubricating characteristics 30 of the lubricant and without materially increasing the corrosive tendencies of such lubricants toward metals in which they come in contact.

Broadly, the invention comprises adding to such extreme pressure lubricants from which an 35 insoluble precipitate or sediment tends to settle out during storage, a small amount of a stabilizer comprising a high molecular weight condensation product of an aromatic compound and a condensable aliphatic compound having more than 40 carbon atoms. Such. compounds are preferably made by Friedel-Crafts condensation of an aromatic hydrocarbon or variousderivatives thereof such as 'those containing low molecular etc., with a relatively long chain aliphatic compound containing a reactive group such as a replaceable halogen. atom or an olefinic linkage, as for instance, chlorinated. parafiin wax, or ole- 5 fins derived therefrom by simple removal of moving metal parts which contact each other hydrogen chloride without substantial cracking of the carbon-to-carbon linkages. Several such materials are available on the market. One, marketed under the trade name Par'aflow, and hereinafter referred to as stabilizer A, is made by condensing about 10-20 parts by weight of naphthalene with 90-80 parts by weight of chlorinated paraflln wax containing about l0% to chlorine, in-the presence of aluminum chloride as catalyst. Anothr material, marketed under the trade name Santopourfl hereinafter referred to as stabilizer B, is made by a similar condensation of phenol with chlorinated paraflin quently referred to as pour depressors, although a number of othermaterials which are pour de- 'pressors do not have the same type of chemical structureas these materials.

I There are also a number of other materials which fall within the scope of the stabilizers of- .this invention. For instance, a suitable mate- .rial, hereinafter referred to as stabilizer C, can

be made by condensing chlorinated paraflin wax with benzene in the presence of aluminum chloride as catalyst. A still diflerent type of material, hereinafter referred to as stabilizer D, is obtained by aluminum chloride condensation of naphthalene with a chlorinated paraflin wax having preferably to of chlorlne;-.which is substantially higher than the chlorine content of the chlorinated paramn wax used for the condeusation mentioned for stabilizer A, the conweight 'alkyl groups such as methyl, ethyl, etc., densation in this instance bein -c ied o t i or other constituents such as hydroxylv groups.

the presence of a chlorinated hydrocarbon sol- Most of the materials of this as refined kerosene.

vent, and the chlorinated parafiln wax being added last to, the reaction mixture. The condensa'tion product in this instance not only has pour-depressing properties such as the other materials mentioned above, but also has the property of increasing the viscosity index of a lubrieating oil base stock to which it is'added.

In preparing the above-described stabilizers, the Friedel-Crafts condensation is preferably carried out in the presence of an inert solvent such.

as a refined naphtha or kerosene, or tetrachlorethane, andis generally carried out at a temperature between. about room temperature and about 300 F., usually being started at room temperature until the initial reaction ratetends to based on the total weight of lubricants, The

' incorporation of sulfur compounds tends to insubside and then the reaction mass is heated to a temperature of about 150 F. or 200 F.-for-about 1-10 hours to 'insure completion of the reaction, I

following which the reaction mass is cooled, preferably after dilution with an inert solvent such The catalyst ishydrolyzed by adding water, alcohol, aqueous caustic soda,

, or a mixture of such agents, and-after settling or centrifuging, the catalyst layer is removed, and the. condensation products, together with solvent or diluent if such were used, are then subjectedto distillation, preferably under re-- duced pressure, such as steam distillation or vacuum distillation under an absolutepressure of about 5-50 mm. of mercury, carrying the distillation up to a temperature of about. 500 F. or 600 F., to obtain the desired high molecular weight condensation product as distillation residue.

This condensation product has a molecular weight above 500, usually above 1,000, and may range as high as 2,000 or 5,000 or higher. It is generally a dark colored .very viscous oily liquid,

soluble in mineral oils. If desired, this'distillation residue may be subjected to solvent extraction with liquids such as propane butane, etc.,

' 'thiocy'anates, etc.

crease the suitability of the lubricant for use under high temperatures, and the sulfur commaterials in which both sulfur and halogen have been incorporated. For instance, a suitable raw material such as paraflln wax or a liquid petroleum distillate such as kerosene, may be treated with a sulfur halide such a sulfur monoor dichloride, in' order to incorporate both sulfur and chlorine. A different method and one which is generally preferred commercially because it permits better technical control, is to chlorinate a suitable raw material such as paraflln' wax, kerosene, or naphtha, to' the desired chlorine content, and then subsequently treat. the resultant compound with sulfur or an inorganic sulfide such as sodium sulflde or polysulfide, or a. mixture thereof with sulfur and sodium hydroxide, or an organic sulfur compound such as methyl alcohol, etc., ethyl acetate, etc., acetone,

etc., in order to obtain a more highly concentrated material as the rafllnate. Substantially all of the lower molecular weight materials being removed and leaving a fraction having especially goodpotency for the stabilizing purposes of the present invention, or for the additional pourgiepresslng or viscosity index improving proper- The amount ;of the stabilizer to beused according to this invention should normally be within the approximate limits of about 0.5% to 15%,

preferably about 2% to 10%, about 5% having x,

been found very suitable.

The extreme pressure lubricant to which the above-described stabilizers may be added accords ins to this invention, may be prepared by incorporating into a mineral oil base stock derived from any of the commonly used crude petroleum oils, a compound containing active halogen and a compound containing active sulfur, or one or a more compounds containing both halogen and sulfur in the same molecules;

I The invention is particularly applicable to extreme pressure lubricants containing corrosive chlorine compounds, for instance, chlorinated aliphatic or aromatic hydrocarbons such a chlorinated derivatives of paraffin wax, kerosene, aromatic petroleum fractions, or coal tar solvents. The amountof chlorine, to'be used, will of course depend upon the severity of the conditions under w ich'the lubricant is to be used butlwill generally vary between the approximate limits'of 1% a d 10% thiocarbonate, xanthate, or thiocyanate.

One example of a suitable extreme pressure lubricating agent is one made by chlorinating kerosene to a chlorine contentof about 25% to 50%, such as 35%, by passing chlorine through kerosene at a temperature of about 175 F. to 200 F., and adding to the resultant chlorinated keroene, an isopropyl alcohol solution of aqueous caustic soda and sodium hydrogen sulfide, con-.

taining free sulfur admixed therewith, using a reflux temperature, for a reaction time ranging. between about hour and 5 or 10 hours. The resultant product may, for instance, contain 7.0%

sulfur and 33% chlorine or, as another example,

might contain 6.5% sulfur and 31% chlorine;-

Ordinarily, the stabilizers of this invention will beneeded more, and therefore be of greatest advantage. when extreme pressure lubricating agents are used which contain a, large amoun of sulfur and chlorine.

A compound made by this method and having this latter composition, and marketed under the trade name Parapoid, will be referred to as Extreme-pressure agent 1," in the tests reported herebelow.

Another example of an extreme pressure lubricating agent whichmay be used is one made by similary chlorinating kerosene to a chlorine content of ab0ut 25% to 50%, preferably about 30% to 40%, and treating the resultant chlorinated kerosene with sodium xanthate, as for instance in alcohol solution. The sodium chloride forms and separates out, and the liquid prodtween the approximate limits of 5% and 50% I, in the chlorinated organic compounds, or be-' for example, which may contain 9% sulphur and 32% chlorine. A compound marketed under the tradename Santopoid, and understood to be made by this procedure, "will be referred to a "Extreme pressure agent 2" in the tests reported herebelow.

Extreme pressure lubricants made by adding to a lubricatingoil base stock separate chlorine and v aseaue sulfur compounds may be made by using about by weight of chlorinated paraflln wax containing 40% to 50% of chlorine, and a sulfur compound, such as benzyl disulfide in sufllcient amount to impart the desired proportion ,of sulfur, for instance 1% based on the total lubricant.

Instead of using benzyl disulflde, of sulfurized sperm oil containing 10% sulfur, might be used. A product of this type is marketed under the trade name Anglamol.

The following tests will further explain how the invention is carried out and will also illustrate the advantages of the invention.

An extreme pressure lubricant stability test was-devised, which comprised placing 50 cubic centimeters of the extreme pressure lubricating agent to be tested, in a pour test jar capped with a slotted cork. For each set of storage conditions to be studied, twosamples of the same a material are tested simultaneously, one simply in contact with the glass of the pour jar and the other containing a strip of unpolished boiler plate sheet iron'(1" x 2" x /4"). As one example of the test storage conditions, the jars are placed 4. Storage in black steel capped pipes under all weather conditions on a building roof, observations being made at 20 and days.

In order to determine whether various chemi- I cal compounds or other materials which might be added to the extreme pressure lubricant, would have any stabilizing eii'ect in preventing the deposition ofa precipitate or sediment or sludge, during storage, the materials to be tested Table I Stability tests after days storage at room temperature Condition 1 of 10% blend in Panhandle B. 8. storage after six days at room temperature simple container Oil layer Other observations Extreme pressure agent 1 Glass...'.. Cloudy... No sediment present.

0... Glass+lron.. do Sit. amt. sediment present. Extreme pressure agent 1+3% stabilizer A. Glass Sit. cloud. No sediment present.

Do..' Glass+iron. .do Do. Extreme pressureagent l+6% stabilizer A Glass do Do. Do .do Do.

TAsLs 11 Stability tests after 60 days storage at 120" F.

Sample Condition l of 10% blend in Panhandle B. S.

. after six days at room temperature Oil layer Other observations Extreme pressure agent 1- No sediment present.

G i Sit. amt. sediment present. Extreme pressure agent 1+3% stabilize A. G. No sediment present.

D G ass+iron-. I n Do. Extreme pressure agent 1+6% stabilizer A- G. Slt. cloud Do. Gim+kn. .d-... Do.

7 1 Observations are made in a 4 oz. oil sample bottle.

in an oven thermostatically controlled at 150 F. TABLE III for 24 hours, then removed and allowed to cool to room temperature. Degradation in solubility is then determined by making a 10% (by weight) blend of each material in a heavy parafllnic oil such as Panhandle Bright Stock (always using the same material for comparative results), observations being made after 5 to 10 days in order to overcome the initial efiect of the blending operation. In the series of tests reported herewith, four different test storage conditions wereused, as follows: I

1. Storage at room temperature in gfass and in the presence of iron, respectively.

2. Storage at 120 F.'for 60 days, observations being made at 20, 40, and 60 days. I

3. Storag at 150 F. for periods of 24, 48, and 120 hours in glass and in the presence of iron.

Stability tests after 40 days storage under weather conditions in iron pipe on roof of building l Observationsare made in a4 0:. all sample bottle. 1 Water is due to leakage of pipes during rainfall.

' Extreme pressure agent 1+6% stabilizer A or in a mineral oil base stock. Y Although the theory as to the exact mechanism Sample Condition 1 of Time of after 5 days at room temperature storage, 4

hours Storage container Oil layer Other observations Extreme pressure agent 1 Extreme pressure agent 1+3% stabilizer A Extreme pressure agent 1+6% stabilizer A... Extreme pressure agent 1 Extreme pressure agent l+3% stabilizer A". Extreme pressure agent 1+6% stabilizer A... Extreme pressure agent 1 Extreme pressure agent 1+3% stabilizer A Extreme pressure agent 1+6% stabilizer A Extreme pressure agent 1 Extreme pressure agent l+3% stabilizer A Extreme pressure agent 1 Extreme pressure agent l+3% stabilizer A... Extreme pressure agent 1+6% stabilizer A. Extreme pressure agent 1 Extreme pressure agent l+3% stabilizer Extreme pressure agent 1+B% stabilizer A ,i

Sediment present. Sit. sediment present.

Do. fi-inch sediment present. sediment present. Slt. amt. sedime t present. M-ingh sedimen present.

Thin slurry of sediment. %-inch sediment present. I ea gy dispersion 0.. a 2.1% inches sediment present. I hin sl oi sediment. -inch sediment present. I

cry heev sediment present. M-inch se iment present.

l t-inch sediment present.

1 Observations are made ii ossible from a 5 oz. oil s'am le bottle. 1 Measurements on the sed ent refer to an accumulat on on the a A dispersion or slurry refers to particle formation which is not extensive enough, or

i i bottom oi the bottle.

the particles are too line to settle in 5 days.

Tenn: V

I Stability tests of extreme pressure lubricants 'made with. 90% of Bright Stock, after 60 hours storage a J I r I K, Condition oi expee lube alter test I RemainingJ a composition (other than 90% Storage Temp. of I Pan andle' Bright Stock) container utorage K I I Oil layer Other observations l 107 extreme pressure agent l. i Hea cloud Preclp. material on sides of bottle. 9.4 a extreme pressure agent l+0.6% stabilizer A Clou r Ve slight-amount of sediment. 107 extreme pressure agent 1 Clear Slig t amount of out present. 0.4 0 extreme pressure agent 1+0.e% stabilizer A. c. No sediment presen I extreme pressure agent 1 "c Slight amount of se ent present. 9.4% extreme pressure agent 1+0.6% stabilizer A .do 150 r Nosediment present.

agent, as wellas the lubricant made therewith,

against development and settling out of an'insoluble precipitate or sludge during storage under various conditions. I

Many other tests yere made, and it was found that the materials described hereinabove and referred to as stabilizers 3,13, and D are all very eil'ective in stabilizing Extreme pressure agent 1 as well as 10% blends thereof in the Panhandle Bright Stock. I

These stabilizers A, B, C, and D may also be used satisfactorily and advantageously in Ex treme pressure agent 2 as well asin blends thereor the operation 01' the invention is not welL bilizer to form a soluble but still 'eflective extreme 1 pressure. molecule. rather than reacting with it.-

self toiform' a higher molecular weight insoluble p o a 1 Inpreparlng extreme pressure-lubricants W cording-'to thisinvention, other known addition agents maybe incorporated if desired. for instance, jetty oils, soaps oi iatty acids or naphth enic acid. other 'materials having. thickeninl,

viscosity-index ,improvingand pour-depressing properties, anti-oxidants, oil-soluble metal soaps,

dyes, etc. 45 It is not intended that this to any 01- the particular examples whichhave been given merely for illustration, nor by any theory as to the mechanism of the operation of the invention, but only by the appended claims ent in the invention as well as other modifications coming within the tion.

' 1. An extreme pressure lubricating agent contaming about 5% to.50% of. chlorine and about 1% to 30% of sulfur. nd derived by chlorinatins a petroleum hydrocarbon fraction and treating the resultant chlorinated hydrocarbon material with a suliurizing agent, to'which has been added a small amount or a condensation product of an aromatic compound and a longaliphatic'fcom pound containingareactive group, said condon sation' product having a molecular weight above 500, being substantially non-volatiles: temper tures up to about.800 1, and -mineral oil.

10% or snliur andabout 25% to 40% '01 chlorine,

. andis m'adeby chlorinating kerosene and treat- I 76 about or a mineral lubricating oil base stock.

10% blend in Panhandle n. s.

invention be limited in which it is intended .to claim all novelty inherscope. and spirit or the invenbeing soluble. in

, 2. Product according toclaim 'ljin-which the i I extreme pressure agent contains about 5% in 3.-An extreme pressure lubricant comnrisins and about 10% of an extreme pressure agent containing about 5% to 10% of sulfur. about 25% to 40% of chlorine and obtained by chlorinating kerosene-and treating the resultant chlorinated kerosene with sodium poLvsulflde as the sulfurizing agent, into which extreme pressure iene with chlorinated paramn wax containing about 10% to 15% oi chlorine, said condensation product having a molecularweight above 1,000, being substantially non-volatile at temperatures up to about 600 F. under reduced pressure. and being soluble'in mineral oil.

EUGENE LIEBER. A LOYSIUB F. CASHMAN. 

